Think of one of the simpler tasks. Say you need to fertilize the trees. When is the right time? What is the right amount? How many people do you need to fertilize 8000 trees in time? How do you finance that, including purchasing the fertilizer? Are you even allowed to purchase that much fertilizer (it's been often abused to make car bombs)?
No idea whether fertilizing is even a thing with coffee, but other tasks won't be much simpler.
If you can't hire one, is taking on a temporary partner (for a cut off the profit) an option?